A chamber used in an extreme ultraviolet light generation apparatus that generates extreme ultraviolet light by irradiating a target material with a laser beam may include a chamber receptacle, a heat shield that is disposed within the chamber receptacle between a predetermined region where the target material turns into plasma and the chamber receptacle and that is configured to absorb heat produced at the predetermined region when the target material turns into plasma, and a support portion configured to attach the heat shield to the chamber receptacle, and further, the support portion may include an absorbing portion configured to absorb stress produced in the heat shield deforming due to the heat, by expanding/contracting in response to the thermal deformation of the heat shield.